Broken Dependency check

Hello. I have placed a small Ruby Project on GitLab [1], i defined a .gitlab-ci.yml [2], but a broken dependency check [3]. What must i change, to make it runnable?

My current file is based on the docu on [4].

[1] https://gitlab.com/saigkill/hoe-manns
[2] https://gitlab.com/saigkill/hoe-manns/blob/master/.gitlab-ci.yml
[3] https://gitlab.com/saigkill/hoe-manns/-/jobs/71403256
[4] https://docs.gitlab.com/ee/ci/examples/dependency_scanning.html